The effect of heat developed during high strain rate deformation on the constitutive modeling of amorphous polymers

• Tipo: Artigo em Revista Científica Internacional
• Data: 2016

Autores

Safari, KH (Autor) Outra; Zamani, J (Autor) Outra; Guedes, RM (Autor) FEUP; Ferreira, FJ (Autor) Outra

Revista

Título: Mechanics of Time-Dependent Materials

Vol. 20

Páginas: 45-64

ISSN: 1385-2000

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 5 Citações

Scopus - 0 Citações

Outras Informações

ID Authenticus: P-00G-SHG

DOI: 10.1007/s11043-015-9283-7

Abstract (EN): An adiabatic constitutive model is proposed for large strain deformation of polycarbonate (PC) at high strain rates. When the strain rate is sufficiently high such that the heat generated does not have time to transfer to the surroundings, temperature of material rises. The high strain rate deformation behavior of polymers is significantly affected by temperature-dependent constants and thermal softening. Based on the isothermal model which first was introduced by Mulliken and Boyce et al. (Int. J. Solids Struct. 43:1331-1356, 2006), an adiabatic model is proposed to predict the yield and post-yield behavior of glassy polymers at high strain rates. When calculating the heat generated and the temperature changes during the step by step simulation of the deformation, temperature-dependent elastic constants are incorporated to the constitutive equations. Moreover, better prediction of softening phenomena is achieved by the new definition for softening parameters of the proposed model. The constitutive model has been implemented numerically into a commercial finite element code through a user material subroutine (VUMAT). The experimental results, obtained using a split Hopkinson pressure bar, are supported by dynamic mechanical thermal analysis (DMTA) and Decompose/Shift/Reconstruct (DSR) method. Comparison of adiabatic model predictions with experimental data demonstrates the ability of the model to capture the characteristic features of stress-strain curve of the material at very high strain rates.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 20